The Molecular and Cellular Pharmacology (MCP) Graduate Training Program at the University of Wisconsin- Madison is entering its 21st year. Its main objectives are to provide training at the predoctoral level in interdisciplinary research at te forefront of Pharmacology, both at the molecular and cellular level, as well as provide a nucleus around which interdepartmental faculty, students, and scientists from across campus can meet and collaborate. The core curriculum is designed to provide graduate students with a foundational knowledge in Pharmacology and enable them to gain experience using cutting edge technologies in the laboratory that will prepare them for careers in academia, industry, government, science education, and public policy. We have identified a core group of 26 dedicated faculty trainers, representing ten departments, whose interests focus on understanding molecular, cellular, and physiological mechanisms by which drugs or natural ligands interact with cellular receptors and elicit effects in biological systems via signal transduction pathways. All trainers have robust research programs supported by extramural funding from the NIH and were selected based on a demonstrated commitment to training graduate students in Pharmacology. The MCP Program is administered by the Center for Training in Pharmacology and Drug Development, which leverages strong support from the School of Medicine and Public Health (SMPH) and the School of Pharmacy (SOP) to provide substantial resources to facilitate the professional development of MCP graduate students. Discovering mechanisms of drug action, defining new approaches to drug delivery, and developing novel drugs as therapeutics are cornerstones of the program, with a major emphasis on understanding pathways that are relevant to disease. MCP faculty members work in the interdisciplinary areas of neuropharmacology, cancer pharmacology, cardiovascular pharmacology, endocrine pharmacology, and antibiotic pharmacology, and collaborate extensively with one another to create a highly interactive network. Coursework for trainees include two semesters of Pharmacology, and one semester each of Cellular Signal Transduction Mechanisms, Molecular and Environmental Toxicology, Grant Writing and Responsible Conduct of Research for Biomedical Graduate Students. All didactic and discussion-based courses are team-taught by experts, focus on quantitative thinking, and involve multiple MCP faculty trainers. MCP students also take a Pharmacology seminar each semester during their graduate training, providing opportunities to develop excellent oral presentation skills, and host student-invited faculty speakers from top institutions across the country. An annual Signal Transduction Symposium offers an additional opportunity for students to host and interact with prominent members of the Pharmacology community and develop networking skills by inviting career panelists from academia, industry, government, patent law and science policy. Over that past 20 years, the MCP program has graduated 95 PhD students, who have gone on to successful careers in all of these areas, with an average time to degree of approximately 5.5 years. The program also boasts considerable trainee diversity, a high retention rate, and an excellent record of trainee publications. In this resubmission, we are requesting 9 training grant slots to support graduate students for 2 years of their early graduate education, a modest increase from the previous period of grant support. This request is based upon the growing demand for PhD level scientists trained in Pharmacology and the high quality of students that regularly apply to the MCP program.